Electronic structures in LaTiO3/LaAlO3 multilayers

摘要

We demonstrate the existence of a hidden degree of freedom controlling the orbital ordering in [LaTiO3]1/[LaAlO3]5 multilayers with comprehensive density-functional theory calculations. The orbitals of two-dimensional (2D) 3d~1 state of Ti atoms in the multilayers always contain large dxy components, which is unexpected from crystal field theory (first Jahn-Teller distortion). The competition between first and second Jahn-Teller distortion induces various magnetic properties. Thus, transition-metal oxides/non-transition-metal oxides multilayers may provide an important direction to manipulate the spin and orbital ordering in magnetic materials.